There's a lot of "us and them" going on here. That is the root cause of racism, not words. That's the point I've made several times, which you dismiss as anaologous to earthquakes and ground shaking.

You're assuming "nigger" means the same to all black people, while meaning something else to white people. That's the problem with your position. You're saying it's part of THEIR dialect. No, it isn't, it's part of OUR dialect, as in English speaking people, and it has a meaning that is generally considered offensive to ALL.

If it's merely part of their dialect, and isn't offensive in the context they use it, is it ok for black children to call each other niggers?

The crazy thing is, if you actually went and asked black people if they found the use of the word offensive, even when exchanged between fellow black people, I am confident that a healthy majority would say yes, it is offensive, and black people should not use the word. So your idea that it is purely dialect is not accurate.